Advanced optoelectronic system architectures and associated methods using spatial light modulation

ABSTRACT

An optoelectronic system includes a concentration layer, a modulation layer including an array of light modulators, an exit layer that receives the modulation layer output having a modulation layer output spatial distribution and remaps the modulation layer output spatial distribution to a modified spatial distribution. A collector layer receives the modified spatial distribution to produce a collector layer output. A detector receives the collector layer output. A processor controls the modulation layer and receives the detector output to generate an image. The collector layer can receive the modified spatial distribution at a plurality of collector layer inputs and combine the plurality of collector layer inputs at a collector layer output. Modulators can be configured to direct couple modulated light to a collector layer, without using an exit layer. Configurations with spatial light modulator modules and sub-modules are described.

RELATED APPLICATIONS

The present application is a divisional of U.S. patent application Ser.No. 16/936,340 entitled ADVANCED OPTOELECTRONIC SYSTEM ARCHITECTURES ANDASSOCIATED METHODS USING SPATIAL LIGHT MODULATION, filed on Jul. 22,2020, which claims priority from U.S. Provisional Patent ApplicationSer. No. 62/878,728 filed on Jul. 25, 2019 and both of which areincorporated herein by reference in their entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

This invention was made with Government support under Grant No. 1852971,awarded by the National Science Foundation. The Government has certainrights in this invention.

BACKGROUND

The present invention is generally related to the field of systems whichutilize light paths, for instance, to modulate light and, moreparticularly, to advanced system architectures and methods for defininga light path.

Applicant recognizes that systems which employ a Spatial Light Modulator(SLM) to receive an incoming beam of light and modify one or morecharacteristics of the light as a function of the cross-sectionalposition within the beam of light are well known. The amount ofmodification and type of characteristic(s) modified can change withrespect to time as well as with respect to position within the beam;this is frequently referred to as modulation. Some example types ofcharacteristics that can be changed in modulating the beam of light areamplitude (intensity), phase, and polarization. Modulation frequently iscontrolled by electrical signals that are supplied to the SLM. It shouldbe noted that the term “light” used throughout this application refersto electromagnetic radiation or Electro-Magnetic Waves (EMW). In someother documentation, the term “light” may be used to only refer to EMWin the visible spectrum. That is not the case in this application;herein the term “light” refers to EMW anywhere in thefrequency/wavelength spectrum that is suitable for modulation by thesystems disclosed herein.

One example of a prior art spatial light modulation system is seen inU.S. Pat. No. 8,941,061 by Gopalsami, et al (hereinafter the '061patent). The '061 patent uses a two lens system in which a single maskprovides for spatial light modulation in a compressive samplingimplementation. In particular, a single mask 301 (FIG. 3) is moved by atwo axis translational stage 303 to provide for different mask patterns.Unfortunately, it is respectfully submitted that moving a large physicalmask in the manner suggested would result in a system that is incapableof generating enough imaging information to be acceptable for practicalapplications such as, for example, real time security applications. Moreimportantly, the use of an imaging lens 305 between mask 301 and animaging target 302, as well as a second lens 311 between mask 301 and adetector 313 is submitted to provide limited flexibility as compared tothe advanced systems yet to be described below.

Another example of a prior art spatial light modulation system is seenin U.S. Pat. No. 8,199,244 by Baraniuk, et al (hereinafter the '244patent). Like the '061 patent, FIG. 1 of the '244 patent discloses asimple two lens system. Instead of using a single physical mask,however, the '244 patent uses a micro-mirror array 140. Again, it issubmitted that such a system would provide limited flexibility ascompared to the advanced systems yet to be described below.

The foregoing examples of the related art and limitations relatedtherewith are intended to be illustrative and not exclusive. Otherlimitations of the related art will become apparent to those of skill inthe art upon a reading of the specification and a study of the drawings.

SUMMARY

The following embodiments and aspects thereof are described andillustrated in conjunction with systems, tools, and methods which aremeant to be exemplary and illustrative, not limiting in scope. Invarious embodiments, one or more of the above described problems havebeen reduced or eliminated.

In general, an optoelectronic system and associated methods aredescribed. In a system embodiment and associated method, the systemincludes a concentration layer including an array of opticalconcentrators, each optical concentrator including a concentrator inputarea and a concentrator output area that is smaller than theconcentrator input area such that each concentrator concentrates aportion of an input light beam received at the concentrator input areainto the concentrator output area. A modulation layer including an arrayof light modulators with each light modulator having a modulator inputarea that is supported in optical communication with the concentratoroutput area of one of the optical concentrators for modulating theportion of the input light beam and the light modulators are spacedapart from one another in the modulation layer to cooperatively producea modulation layer output having a modulation layer output spatialdistribution. An exit layer receives the modulation layer output havingthe modulation layer output spatial distribution and remaps themodulation layer output spatial distribution to a modified spatialdistribution. A collector layer receives the modified spatialdistribution to produce a collector layer output. At least one detectorreceives the collector layer output to generate a detector outputtherefrom. A processor is configured for controlling the modulationlayer and for receiving the detector output to generate an image basedon the input light beam.

In another system embodiment and associated method according to thepresent disclosure, an optoelectronic system includes a concentrationlayer including an array of optical concentrators, each opticalconcentrator including a concentrator input area and a concentratoroutput area that is smaller than the concentrator input area such thateach concentrator concentrates a portion of an input light beam receivedat the concentrator input area into the concentrator output area. Amodulation layer includes an array of light modulators with each lightmodulator having a modulator input area that is supported in opticalcommunication with the concentrator output area of one of the opticalconcentrators for modulating the portion of the input light beam and thelight modulators are spaced apart from one another in the modulationlayer to cooperatively produce a modulation layer output having amodulation layer output spatial distribution. An exit layer receives themodulation layer output having the modulation layer output spatialdistribution and remaps the modulation layer output spatial distributionto a modified spatial distribution. A collector layer receives themodified spatial distribution at a plurality of collector layer inputsand combines the plurality of collector layer inputs to a single wavepassage at a collector layer output to serve as a combined collectorlayer output. A detector receives the combined collector layer outputfrom the single wave passage. A processor is configured for controllingthe modulation layer and for receiving the detector output to generatean image based on the input light beam.

In still another system embodiment and associated method according tothe present disclosure, an optoelectronic system includes aconcentration layer including an array of optical concentrators, eachoptical concentrator including a concentrator input area and aconcentrator output area that is smaller than the concentrator inputarea such that each concentrator concentrates a portion of an inputlight beam received at the concentrator input area into the concentratoroutput area. A modulation layer includes an array of light modulatorsthat are spaced apart from one another in the modulation layer formodulating each portion of the input light with each light modulatorhaving: (i) a modulator input area in optical communication with theconcentrator output area of one of the optical concentrators, and (ii) amodulator waveguide for receiving the modulated portion of light andexternally outputting the modulated portion of light. A collectorwaveguide defines a waveguide input for the modulator waveguide of eachlight modulator in the array of light modulators and the collectorwaveguide combines the outputted modulated portion of light from eachlight modulator with the outputted modulated portion of light from otherones of the light modulators in the array of light modulators to producea collector waveguide output. A detector receives the collectorwaveguide output to produce a detector output. A processor is configuredfor controlling the modulation layer and for receiving the detectoroutput to generate an image based on the input light beam.

In yet another system embodiment and associated method according to thepresent disclosure, an optoelectronic system includes a plurality ofspatial light modulation sub-modules for receiving input light,modulating the input light to produce modulated light and outputting themodulated output light, the sub-modules supported in a side-by-siderelationship. A combiner combines the modulated output light from two ormore of the sub-modules to produce at least one combined output. Atleast one detector receives the combined output to generate a detectoroutput. A processor is configured for controlling the plurality ofspatial light modulation sub-modules and for receiving the detectoroutput to generate an image based on the input light.

BRIEF DESCRIPTIONS OF THE DRAWINGS

Example embodiments are illustrated in referenced figures of thedrawings. It is intended that the embodiments and figures disclosedherein are to be illustrative rather than limiting.

FIG. 1 is a diagrammatic view, in elevation, illustrating an embodimentof an optoelectronic system produced in accordance with the presentdisclosure.

FIG. 2 is a diagrammatic view, in elevation, of another embodiment of anoptoelectronic system produced in accordance with the present disclosureincluding a concentration layer and an exit layer each of which is madeup of side-by-side horns and a lens serving as a collector layer.

FIG. 3 is a diagrammatic view, in elevation, of another embodiment of anoptoelectronic system produced in accordance with the present disclosureand which resembles the optoelectronic system of FIG. 2 except that ahorn serves as the collector layer.

FIG. 4 is a diagrammatic partially cutaway view, in perspective, ofanother embodiment of an optoelectronic system produced in accordancewith the present disclosure.

FIG. 5 is a diagrammatic partially cutaway view, in perspective, ofanother embodiment of an optoelectronic system produced in accordancewith the present disclosure and which resembles the structure of theoptoelectronic system of FIG. 4 with the exception of a plurality ofhorns in a first section of a collector layer that couple to a secondsection of the collector layer to guide the modulated light to adetector.

FIG. 6 is a diagrammatic partially cutaway view, in perspective, ofanother embodiment of an optoelectronic system produced in accordancewith the present disclosure and which resembles the structure of theoptoelectronic system of FIG. 4 with the exception of a plurality ofhorns in the collector layer which couple modulated light to a pluralityof detectors.

FIG. 7 a is a diagrammatic partially cutaway view, in perspective, ofanother embodiment of an optoelectronic system produced in accordancewith the present disclosure in which a concentration layer is made up ofan array of lenses.

FIG. 7 b is a diagrammatic partially cutaway view, in perspective, ofanother embodiment of an optoelectronic system produced in accordancewith the present disclosure and which resembles the optoelectronicsystem of FIG. 7 a except that the exit layer, like the concentrationlayer, is made up of an array of lenses.

FIG. 8 is a diagrammatic partially cutaway view, in perspective, ofanother embodiment of an optoelectronic system produced in accordancewith the present disclosure and which resembles the optoelectronicsystem of FIG. 4 except that a lens serves as the collector layer.

FIG. 9 a is a diagrammatic partially cutaway view, in perspective, of acollector layer produced in accordance with the present disclosureutilizing an array of horns and a collector waveguide and which can beused at least in place of the collector layers used in theoptoelectronic systems of FIGS. 4, 5, 7 and 8 .

FIG. 9 b illustrates additional details with respect to the collectorlayer of FIG. 9 a in a diagrammatic exploded view, in perspective, andin relation to a detector.

FIGS. 9 c and 9 d illustrate additional details with respect to thecollector layer of FIGS. 9 a and 9 b in diagrammatic partially cutawayperspective views, showing the horn layer and the collector waveguide,respectively, in isolation.

FIG. 9 e is a diagrammatic partially cutaway view, in perspective, ofanother collector layer which resembles the collector layer shown inFIGS. 9 a-9 d with the exception that passages of the collectorwaveguide are filled with a dielectric material.

FIG. 9 f is a diagrammatic partially cutaway view, in perspective, ofanother collector layer which resembles the collector layer shown inFIGS. 9 a-9 d with the exception that the array of horns has beenreplaced by an array of lenses and associated supports.

FIG. 10 is a diagrammatic partially cutaway view, in perspective, ofanother embodiment of an optoelectronic system produced in accordancewith the present disclosure and which resembles the optoelectronicsystem of FIG. 4 at least given that that there is no exit layer since adielectric post serves to transfer modulated light from each lightmodulator directly to a collector waveguide.

FIG. 11 is a diagrammatic partially cutaway and exploded view, inperspective, of the optoelectronic system of FIG. 10 , shown here toillustrate additional details of its structure.

FIG. 12 is a diagrammatic view, in perspective, illustrating anotherembodiment of an optoelectronic system produced in accordance with thepresent disclosure including a spatial light modulator that receivesinput light from a concentration layer and subjects the concentratedlight to blocking patterns produced using a flexible tape media.

FIG. 13 is another diagrammatic view, in perspective, illustratingadditional details with respect to the embodiment of FIG. 12 , shownhere to illustrate additional details of its structure and operation.

FIG. 14 is a diagrammatic partially cutaway view, in perspective,illustrating four collector waveguides side-by-side for use as part ofan overall system including a detector associated with each collectorwaveguide.

FIG. 15 is a diagrammatic partially cutaway view, in perspective,illustrating four collector waveguides side-by-side for use as part ofan overall system including a supplemental waveguide that couples fromthe collector waveguides to a detector.

DETAILED DESCRIPTION

The following description is presented to enable one of ordinary skillin the art to make and use the invention and is provided in the contextof a patent application and its requirements. Various modifications tothe described embodiments will be readily apparent to those skilled inthe art and the generic principles taught herein may be applied to otherembodiments. Thus, the present invention is not intended to be limitedto the embodiments shown, but is to be accorded the widest scopeconsistent with the principles and features described herein includingmodifications and equivalents, as defined within the scope of theappended claims.

Applicants hereby describe advanced passive or active imaging systemarchitectures and associated methods which use spatial light modulation.Embodiments of the systems described herein support compressive samplingand imaging with electromagnetic waves (EMW) over a range of frequenciesfrom 10 GHz to 10 THz (millimeter wave to terahertz spectrum), as wellas over a range of frequencies from 30 GHz to 300 GHz (millimeter wavespectrum). In conjunction with a compressive sampling algorithm or othersuitable algorithm for collecting data to render an image, disclosedsystems comprise a millimeter wave imaging camera offering sweepingimprovements over the state-of-the-art in millimeter wave imaging.

Turning now to the drawings, it is noted that the figures are not toscale and are diagrammatic in nature in a way that is thought to bestillustrate features of interest. Descriptive terminology such as, forexample, upper/lower, top/bottom, horizontal/vertical, left/right andthe like, may be adopted with respect to the various views provided inthe figures for purposes of enhancing the reader's understanding and isin no way intended to be limiting. All embodiments described herein aresubmitted to be operational irrespective of any overall physicalorientation. It is noted that like reference numbers may be used torefer to like items throughout the various figures.

FIG. 1 is a diagrammatic view illustrating an embodiment of anoptoelectronic system, generally indicated by the reference number 10and produced in accordance with the present disclosure. It is initiallynoted that suitable measures can be taken to enhance energy transferbetween the various layers and components in the systems yet to bedescribed. Such measures include but are not limited to impedancematching based on dimensional considerations, antireflective materialsor layers, meta-materials, and permittivity of the materials used in thevarious components. System 10 is shown imaging a scene 12 that islaterally spaced away from the system and normal to the plane of thefigure such that the scene is represented by a line. Input light or EMW20 from the scene is represented as an arrow traveling toward aconcentration layer 30. It is noted that scene 12 can be activelyilluminated with light at a wavelength or range of wavelengths ofinterest, however, this is not a requirement. Embodiments ofconcentration layer 30 include an array of optical concentrators,diagrammatically shown as rectangles making up the concentration layerand several of which are individually designated by the reference number34. From a functional perspective, each optical concentrator includes aconcentrator input area 38 and a concentrator output area 40 that issmaller than the concentrator input area such that each concentratorconcentrates a portion 42 (demarcated by dotted lines) of input lightbeam 20 received at the concentrator input area into one, respectiveconcentrator output area 40. A concentrated output 44 is individuallydesignated for several of the concentrators and represented by an arrow.Side-by-side rows and/or columns of the concentrator array can be offsetwith respect to one another in order to increase the relative amount ofinput light that is incident upon the concentrator input areas, forexample, when the concentrator input areas are circular in shape. Ofcourse, components of any subsequent layers can be arranged in a waythat matches up or aligns with the arrangement of concentrators used inthe concentration layer. While embodiments of the concentration layerwill be described in detail below, it is initially noted that someembodiments externally transfer concentrated outputs 44 to an ambientenvironment or atmosphere surrounding the system such as, for example,air or the vacuum of space while other embodiments externally transferconcentrated outputs without emission into an ambient environment, forexample, using a waveguide to conduct the concentrated outputs to asubsequent layer.

Still referring to FIG. 1 , concentrated outputs 44 are received byindividual modulators 48 that make up an array of modulators in amodulation layer 50. The array can be of any suitable dimensions interms of width and length (i.e., rows and columns) transverse or normalto the direction of travel of input light 20 and concentrated outputs44. It is noted that the array configuration can be carried from theconcentration layer through the modulation layer and subsequent layers,as needed. Side-by-side rows and/or columns of the array can be offsetwith respect to one another. The modulators can be of any suitable type,either currently available or yet to be developed, that are electricallycontrollable by a processor 54 through a control line 58. Suitable typesof modulators include but are not limited to magneto-optic,electro-optic such as Pockel cells, electrochromic, polarizationmodulation using graphene, mechanical shutters, metamaterial (see, forexample, a publication by Claire M. Watts, et al., entitled TerahertzCompressive Imaging with Metamaterial Spatial Light Modulators, NaturePhotonics, Vol. 8, August 2014). One suitable array of magneto-opticmodulators is described as part of the spatial light modulator disclosedin U.S. Pat. No. 10,345,631, entitled SOLID STATE SPATIAL LIGHTMODULATOR, which is hereby incorporated by reference. Other suitablemodulators are disclosed in U.S. patent application Ser. No. 16/936,319,now issued as U.S. Pat. No. 11,378,829, entitled ADVANCED SPATIAL LIGHTMODULATORS, ASSOCIATED SYSTEMS AND METHODS, which is commonly owned withthe present application and filed on the same day as the presentapplication. Each modulator provides a modulator output 60, several ofwhich are individually designated. It should be appreciated that theoutput of the modulation layer can be characterized by a modulationlayer spatial output distribution wherein such a distribution isestablished by the lateral distribution of the spaced apart modulatoroutputs 60 from the array of modulators. In the present example, themodulation layer spatial output distribution is non-uniform across thelateral extents of the modulation layer.

In the embodiment of FIG. 1 , modulator outputs 60 are received by anexit layer 64. The latter serves to receive the modulation layer outputhaving the modulation layer output spatial distribution. It is notedthat the modulator outputs are, of course, modulated and shown as beingequal in size (as may be the case throughout the various figures),although it is understood that this generally will not be the case dueto the impressed modulation. For example, some of the modulators can beset to block the input light based on a particular blocking pattern thatis being impressed on the modulators of the modulation layer. The exitlayer further serves to remap or redistribute the modulation layeroutput spatial distribution to a modified spatial distribution 68 which,in the present example, is more uniform and wider in lateral extentsthan the modulation layer spatial output distribution. For illustrativepurposes, the modified spatial distribution is shown as being made up ofa plurality of uniformly distributed waves 70, several of which areindividually designated. It is noted that waves 70 can be laterallyuniformly distributed at least to a reasonable approximation. Modifiedspatial distribution 68 is then received by a collector layer 80. Whilesome embodiments of the collector layer may best function when a moreuniform modified spatial distribution is received, it should beappreciated that, in some embodiments, the exit layer can be configuredto produce a modified spatial distribution that is customized to therequirements of the exit layer, such that the modified spatialdistribution is not necessarily more uniform, in contrast with themanner illustrated.

Collector layer 80 serves to receive the modified spatial distributionto produce a collector layer output 84 that is directed to or focusedtoward a detector 88. The detector can be of any suitable type eithercurrently available or yet to be developed including, but not limited toa tunnel diode type, Dicke-switched radiometer, and bolometer, and canbe configured dependent upon the wavelength range that is of interest.It is noted that the detector can include a small impedance matchinghorn 89 which is shown in phantom using dotted lines, although this isnot a requirement. The collector layer output is made up of a pluralityof redirected waves 90, several of which are individually designated. Insome embodiments, a plurality of detectors can be used with thecollector layer customized to divide modified spatial distribution 68into a portion for each detector. In some embodiments, exit layer 64 cancooperate with a customized collector layer by beginning to divide themodified spatial distribution into the portions that are to ultimatelybe received by detectors.

Under the control of processor 54, modulation layer 50 can be driven inany suitable manner while obtaining outputs from detector 88 forpurposes of generating an image that can be presented on a display 92.An associated input device 94 allows an operator to provide inputs toprocessor 54. Of course, the image can readily be externallytransferred, for example, through an Internet connection 96. In acompressive sensing embodiment, the modulation layer can be driven toproduce a series of masks or blocking patterns with an output read fromdetector 88 in association with each blocking pattern. These outputs canthen be used to generate an image on display 92. Prior art examples ofblocking patterns include Hadamard patterns, although any suitableblocking patterns can be used. In this regard, the disclosed systems caneven be configured to generate image data serially on a pixel-by-pixelbasis in a way that mimics conventional imaging sensors such as, forexample, a CMOS sensor which collects pixel values essentially inparallel.

Having described FIG. 1 in detail, it is noted that the various layers,at least from a functional perspective, are illustrated in a spacedapart relationship for illustrative clarity and for purposes ofenhancing the reader's understanding. In some embodiments, however, itwill be seen that some amount of physical overlap can be present withrespect to adjacent functional layers.

FIG. 2 is a diagrammatic, more detailed illustration of an embodiment ofa system produced in accordance with the present disclosure andgenerally indicated by the reference number 100. In this embodiment, aconcentration layer 104 is made up of side-by-side individual horns 108.Each horn of the present embodiment, as well as the horn(s) of otherembodiments described throughout the present disclosure, can include anysuitable cross-sectional shape such as, for example, circular. In thisexample, the individual horns are frustoconical. Another suitablecross-sectional shape is rectangular which also encompasses a squareshape. Any suitable shape can also be used for the sidewall(s) along thelength of each horn 108. For example, the straight sidewalls of afrustoconical or truncated cone shape can be used. As another example,the sidewalls can include a nonlinear, curved or arcuate shape.

The horns described throughout this disclosure can be configured torespond to different polarities of light. For example, a square orrectangular horn is more responsive to a linear polarization, therebypartially acting as a polarizer in addition to the concentration layer.A circular horn is more responsive to all polarizations, thereby onlyconcentrating the light.

An exit layer 110 includes an array of side-by-side individual horns 120having an entrance opening 124 facing the modulation layer and arelatively larger exit opening 128 at an opposing end. It is noted thatthere is no requirement for horns 120 of exit layer 110 to be of thesame size and/or shape as horns 108 of the concentration layer. In thepresent embodiment, horns 120 are configured to emit uniformlydistributed waves 70 although other configurations of the horns canproduce a non-uniform distribution, if needed. It is also noted that aone-for-one correspondence between horns 120 and modulators 48 is notrequired such that one horn can receive the output from a plurality ofmodulators.

Still referring to FIG. 2 , a collector layer 130 includes a convex orconverging lens 134 that is configured to receive uniformly distributedwaves 70 and focus redirected waves 90 on detector 88 which ispositioned to place the detector at least approximately at a focal pointof the lens. Lens 134 can be formed in any suitable manner from anysuitable material including, but not limited to high densitypolyethylene.

FIG. 3 is another diagrammatic, more detailed illustration of anembodiment of a system produced in accordance with the presentdisclosure and generally indicated by the reference number 200. It isnoted that system 200 replicates the structure of system 100 with theexception that, in this embodiment, a collector layer 204 includes acollector horn 210 having an input 214 which receives uniformlydistributed waves 70 and produces output waves 220 at an output 224 thattravel to detector 88. As shown, input 214 is larger in lateral extentsthan output 224. Collector horn 210 can be formed in any suitable mannerfrom suitable materials including, but not limited to brass, aluminum,steel, or metal-coated plastic, such as nickel-plated plastic. In someembodiments, there is no interstitial space present between the outputof collector horn 210 and the input of detector 88, although this is nota requirement. The collector horn can be any suitable shape in itslateral extents, for example, based on the lateral extents of exit layer110 and modulation layer 50.

Still referring to FIG. 3 and in some embodiments, a medium 230 (onlypartially shown) can be present in an interstitial space (i.e.,interstice) between exit layer 110 and collector layer 204. While not arequirement, the medium can also be present in the body or interiorcavity of horns 108 and/or in the body or interior cavity of horn 210 ofthe collector layer. It is noted that suitable coatings can be appliedto any outwardly facing surface(s) of the medium for purposes ofimpedance matching such as, for example, an antireflective coating.Suitable materials for medium 230 include but are not limited to mylar,HDPE, multi-layer materials, and any other material(s) that issubstantially transmissive at desired wavelength(s) and has a dielectricconstant larger than 1. It is noted that the interior cavity of any ofthe horns described throughout this disclosure can contain a medium andappropriate coatings. Referring briefly again to FIG. 2 , medium 230 canbe present in a similar manner between horns 120 and lens 134, althoughthis is not a requirement.

Attention is now directed to FIG. 4 which is a diagrammatic cutawayview, in perspective, of a system produced in accordance with thepresent disclosure and generally indicated by the reference number 400.Input light 20 is illustrated as a series of arrows. It is noted thatthe basic structure of system 400 resembles that of system 200 of FIG. 3. System 400 includes a concentration layer 404 having an array ofconcentrator horns, several of which are individually designated by thereference number 408. It is noted that the dimensions of the arrays(i.e., rows and columns) carrying through the structure of system 400can be of any suitable size, although FIG. 4 is representative of a 3×3array in consideration that one-half of the structure has been cut-awayin the view of the figure. Processor 54 has not been shown for purposesof illustrative clarity but is understood to be present. Each horn caninclude a main portion 410 and an exit port 414 extending from the mainbody that is tubular with a uniform cross-sectional shape and dimensionsalong the length of the exit port. It is noted that the term “tubular”,as used herein, does not require a cylindrical shape but instead refersto any suitable cross-sectional shape. In the present embodiment, themain portion of each horn and the exit port are at least generallysquare in lateral cross-section with chamfered corners, although this isnot required. The horn bodies and exit ports of the present example alsoinclude chamfered corners 418, several of which are individuallydesignated. The concentration layer can be integrally formed from asingle layer of a suitable material such as, by way of non-limitingexample, brass, aluminum, steel, or metal-coated plastic.

A modulation layer 420 includes an array of modulators, several of whichare individually designated by the reference number 424 in a one-to-onecorrespondence with concentrator horns 408. Each modulator 424, by wayof non-limiting example, includes a Faraday element 428 that issurrounded by an electrical coil 430. A printed circuit board 432 cancarry control signals from processor 54 (see FIG. 4 ) to the coil ofeach modulator for control purposes. An upper dielectric post 434 caninclude a cylindrical shape with one end received within the exit portof one of horns 408 and an opposing end received in a central apertureof coil 430 adjacent to Faraday element 428. In an embodiment, the upperend of dielectric post 434 can extend into main portion 410. A lowerdielectric post 440 can also include a cylindrical shape with one endreceived in the central aperture of coil 430 adjacent to an opposite endof Faraday element 428. A lower, opposite end of dielectric post 440 canbe received within an exit layer, as will be described below. In anembodiment, the dielectric post can include a peripheral outline(s) thatis complementary to the component in which it is received. As notedabove, the dielectric posts can be jacketed by a layer of electricallyconductive material or unjacketed. Further, dielectric posts inembodiments of the disclosure can be of any suitable shape in lateralextents and are not limited to a cylindrical shape. Such dielectricposts can be unjacketed dielectric material or a jacketed dielectricmaterial. Insofar as workable dielectric materials are concerned, anymaterial that has a dielectric constant greater than the surroundingatmosphere or ambient can be utilized. Suitable materials include butare not limited to alumina, ferrite, and HDPE. For use as the jacket,any suitable conductive material can be used, such as, for example,aluminum, stainless steel, nonmagnetic steel, gold, gold-plated plasticor plastic coated with nickel and then gold.

Still referring to FIG. 4 , an exit layer 450 is partially cutaway toreveal the structure of one row of three exit horns 454. The structure,in this example, is used to support printed circuit board 432. In anembodiment, the exit layer can be a mirror image of concentration layer404, although this is not a requirement and is not the case in thepresent embodiment. Each exit horn 454 includes an entrance port 458 anda main portion 460 such that a lower end of each lower dielectric post440 is received within entrance port 458 of one of exit horns 454. It isnoted that collimation can be enhanced by horns 460, or any horn forthat matter, by making the horn relatively longer along the propagationdirection and/or relatively more narrow transverse to the propagationdirection. Thus, uncollimated modulated light 461 can be collimated asthe light travels through the horn. In some embodiments, the lower endof dielectric post 440 can extend into main portion 460. In the presentembodiment, exit horns 454 are of the same general configuration asconcentration layer horns 408, however, entrance ports 458 includelateral extents that are of reduced dimensions as compared to exit ports414 of the concentration layer. In a manner that is consistent with theillustration of FIGS. 1 and 3 , the output from exit layer 450 will havea distribution 462 (represented by arrows) that can be more uniformlaterally than the modulated distribution from modulators 424 ofmodulation layer 420. Like concentration layer 404, exit layer 450 canbe integrally formed from a suitable material, although this is not arequirement. Distribution 462 is received by a collector layer 470. Inthe present embodiment, the collector layer includes a single collectorhorn 474 that couples the light of the distribution to detector 88 via amain portion 478. Detector 88 can include an entrance aperture 480 whichforms part of a housing for the detector. As noted, the latter can beany suitable type of detector or sensor including a sensing element 484and support electronics 488 to produce an output 500 that can be used bya processor.

Referring to FIG. 5 , a diagrammatic partially cutaway view, inperspective, of another embodiment of a system configured in accordancewith the present disclosure is shown and generally indicated by thereference number 600. It is noted that the dimensions (i.e., rows andcolumns) of the arrays carrying through the structure of system 600 canbe of any suitable size, although FIG. 5 is representative of a 4×3array in consideration that one-half of the structure has been cut-awayin the view of the figure. System 600 is identical to system 400 of FIG.4 with the exception of a collector layer 610. In the presentembodiment, the collector layer is made up of two sections. A firstsection 614 defines a pair of adjacent collector horns 618 each one ofwhich receives a portion of modulated output distribution 462. Inparticular and by way of non-limiting example, each collector hornreceives the output of six modulators 424 (i.e., one-half of the array)via exit horns 454. Each collector horn can serve any suitable number ofmodulator outputs while remaining within the scope of the teachingsherein. Insofar as their physical structure and shape, collector horns618 can be configured in any suitable manner in a way that is consistentwith the descriptions above. A portion of modulated light energy 462 iscarried by each collector horn 618 to a collector horn output 620. Asecond section 624 of the collector layer is configured as a waveguideincluding a passage 630 that extends from each collector horn output 620to detector 88. Of course, collector horns 618 can be impedance matchedto waveguide passages 630, for example, based on the shape of the exitopening of each horn 618 in cooperation with the shape of the entranceto each passage 630. In this regard, passages 630 are illustrated asbeing of uniform dimensions along their length, however, this is not arequirement.

FIG. 6 is a diagrammatic cutaway view, in perspective, of an embodimentof a system configured in accordance with the present disclosure andgenerally indicated by the reference number 700. It is noted that system700 is identical to system 600 of FIG. 5 with the exception of acollector layer 710. The latter does not utilize waveguide 624 section.For purposes of the present description, the horns of collector layer710 have been individually designated by appending an “a” or “b” to theappropriate reference numbers carried forward from FIG. 5 . Thus, horns618 a and 618 b are shown with respective horn exits 620 a and 620 b.These horn exits are individually coupled to respective detectors 88 aand 88 b. Outputs 500 a and 500 b each serve one-half of the array andcan be read by processor 54 and combined by the processor to serve as anoverall output. Based on FIG. 6 , it should be appreciated that anysuitable number of detectors can be used with a high degree offlexibility based, for example, on the dimensions of the array that isserved.

Turning to FIG. 7 a , a diagrammatic cutaway view, in perspective, isillustrated of another embodiment of a system configured in accordancewith the present disclosure and generally indicated by the referencenumber 800. Initially, it is noted that collector layer 470 wasinitially illustrated in FIG. 4 and described with regard thereto. Inputlight 20 is received by a concentration layer 804. Within each one of aplurality of an array of dome housings 808, each one of a correspondingarray of convex lens 810 focuses a portion of input light 20 toward anexit aperture 814 that leads to a light modulator 424. In the presentembodiment, lenses 810 and dome housings 808 include a complementaryperipheral shape such that each lens can be received at the remote endof an interior cavity defined by one of the dome housings. The lensescan be held in position, for example, by a suitable adhesive. The domehousings and lenses are circular in lateral cross-section although anysuitable shape can be used. Each dome housing of the present embodimentincludes a conical horn 818 that leads to exit aperture 814. It is notedthat the conical horns are not required given the presence of convexlenses 810 which serve to focus input light into apertures 814. Domehousings 808 can be formed from a suitable material that issubstantially transparent to the wavelength(s) of interest such as, forexample, plastic. Convex lenses 810 can be formed from a suitablematerial that is also substantially transparent and refractive to thewavelength(s) of interest, including but not limited to plastic, HDPE,and any other suitable material that is substantially transmissive atthe desired wavelength(s) and has a dielectric constant greater than 1in the wavelengths of interest. If desired, an electrically conductivecoating can be applied to the interior surface of each conical horn, forexample, if the dome housing is molded from a plastic material. Eachlight modulator 424 modulates a portion of the input light and outputsthe modulated light to an exit layer 820 which includes an array of exithorns 460 for producing distribution 462 that is then routed to detector88.

Attention is now directed to FIG. 7 b which is a diagrammatic partiallycutaway view, in perspective, of a system produced in accordance withthe present disclosure and generally indicated by the reference number840. It is noted that the structure of system 840 resembles that ofsystem 800 of FIG. 7 a with the exception of an exit layer 850. Hence,the present discussions will be limited to describing exit layer 850insofar as practical without repeating descriptions of previouslydescribed components. Essentially, exit layer 850 is made up of an arrayof convex lenses 854, as will be described in further detail immediatelyhereinafter.

After modulation of input light 20 by each light modulator 424,modulated light 858 enters an exit aperture 856 that leads to an exithorn 860. In some embodiments, exit aperture 856 can receive adielectric post that terminates within the exit aperture or extends intothe exit horn in a manner that is consistent with the descriptionsabove. In the present example, horns 860 are conical. It is noted thatthe modulated light can be uncollimated within horns 860, asillustrated. One of lenses 854 can be supported within each one of aplurality of an array of dome housings 864, to redirect light 858 intodistribution 462 for receipt by collector layer 470. Depending at leastin part on the configuration of lenses 854, it should be appreciatedthat distribution 462 can be customized in its lateral extents. In thepresent embodiment, distribution 462 is more collimated than modulatedlight 858 while at least approximately matching the lateral extents ofthe array of lenses 854. In other embodiments, distribution 462 can begreater in lateral extents (i.e., arrows making up distribution 462diverging) or lesser in lateral extents (i.e., arrows making updistribution 462 converging) than the lateral extents of the array oflenses 854. As examples, a diverging distribution 462′ is illustrated bydotted diverging arrows while a converging distribution 462″ isillustrated by converging dotted arrows. It is noted that thesecustomized distributions can be implemented based on horns rather thanlenses. In the present embodiment, lenses 854 and dome housings 864include a complementary peripheral shape such that each lens can bereceived at the remote end of an interior cavity defined by one of thedome housings. The lenses can be held in position, for example, by asuitable adhesive. The dome housings and lenses can be circular inlateral cross-section although any suitable shape can be used. It isnoted that the conical horns are not required given the presence ofconvex lenses 854. Dome housings 864 can be formed from a suitablematerial that is substantially transparent to the wavelength(s) ofinterest such as, for example, plastic. Convex lenses 854 can be formedfrom a suitable material that is also substantially transparent andrefractive to the wavelength(s) of interest, including but not limitedto plastic, HDPE, and any other suitable material that is substantiallytransmissive at the desired wavelength(s) and has a dielectric constantgreater than 1 in the wavelengths of interest. If desired, anelectrically conductive coating can be applied to the interior surfaceof each conical horn, for example, if the dome housing is molded from aplastic material.

FIG. 8 is a diagrammatic partially cutaway view, in perspective, ofanother embodiment of a system configured in accordance with the presentdisclosure and generally indicated by the reference number 900.Initially, it is noted that concentration layer 404, modulation layer420 and exit layer 450 are essentially the same as the correspondinglayers shown originally in FIG. 4 . The reader is referred to thedescriptions of these layers which appear above and such descriptionswill not be repeated for purposes of brevity. It is also noted thatdetector 88 is unchanged with respect to its appearance in FIG. 4 .Collector layer 920, however, includes a dome housing 924 which receivesand supports a convex lens 928. The latter focuses distribution 462toward an exit aperture 480 and sensor 484. Like the correspondingcomponents in FIG. 4 , lens 928 and dome housing 928 can include acomplementary peripheral shape such that the lens can be received at theremote end of an interior cavity defined by the dome housing. The lenscan be held in position, for example, by a suitable adhesive. The domehousing and lens are circular in lateral cross-section although anysuitable shape can be used. The dome housing of the present embodimentcan include a conical horn 930 that leads to exit aperture 480. Theconical horn is not required given the presence of convex lenses 928which can serve to focus input light directly to sensor 484. Domehousing 924 can be formed from a suitable material that is substantiallytransparent to the wavelength(s) of interest such as, for example,plastic. Convex lens 928 can be formed from a suitable material that isalso substantially transparent and refractive to the wavelength(s) ofinterest, including but not limited to plastic, HDPE, and any othersuitable material that is substantially transmissive in the desiredwavelength and has a dielectric constant larger than 1. If desired, anelectrically conductive coating can be applied to the interior surfaceof the conical horn, for example, if the dome housing is molded from aplastic material.

Referring to FIG. 9 a , a diagrammatic partially cutaway view, inperspective, of a collector layer is illustrated, generally indicated bythe reference number 1000. FIG. 9 b is a diagrammatic exploded view, inperspective, of collector layer 1000 shown in relation to detector 88.It is noted that collector layer 1000 can be used at least in place ofcollector layer 470 of FIGS. 4 and 7 , collector layer 610 of FIG. 5 andcollector layer 920 of FIG. 8 . Collector layer 1000 can also be adaptedfor use in a wide range of embodiments such as, for example, ascollector layer 710 of FIG. 6 in view of the teachings that have beenbrought to light herein. While a number of through holes/apertures arevisible, it should be appreciated that these features are provided, forexample, to receive fasteners that are not shown.

In FIG. 9 a , previously described exit layer output distribution 462 isshown as being incident on collector layer 1000 from the associated exitlayers seen in FIGS. 4, 5 and 7 . The collector layer includes a hornlayer 1004 which defines an array of horns, several of which areindividually designated by the reference number 1008. Horn layer 1004 isalso shown, in perspective, in the diagrammatic, partially cutaway viewof FIG. 9 c which is taken generally along a line 9 c-9 c shown in FIG.9 b . It is noted that the dimensions of horn layer 1004 (i.e., rows andcolumns) can be of any suitable size, although FIG. 9 a isrepresentative of an 8×8 array in consideration that slightly less thanone-half of the structure of horn layer 1004 has been cut-away in theview of the figure for purposes of illustrative clarity. Each horn 1008can include a main portion 1010 and an exit port 1014 extending from themain body that is tubular with a uniform cross-sectional shape anddimensions along the length of the exit port. In the present embodiment,the main portion of each horn and the exit port are at least generallysquare in lateral cross-section, although this is not required. The hornbodies and exit ports of the present example can also include chamferedor rounded corners 1016. In some embodiments, the horn layer can beintegrally formed from a single layer of a suitable material such as, byway of non-limiting example, brass, aluminum, steel, or metal-coatedplastic.

Referring to FIG. 9 d in conjunction with FIGS. 9 a and 9 b , the formeris a diagrammatic partially cutaway view, in perspective, takengenerally along a line 9 d-9 d shown in FIG. 9 b to illustrate detailswith respect to a collector waveguide 1020 which forms part of collectorlayer 1000. It is noted that FIG. 9 d illustrates one-half of collectorwaveguide 1020. As seen in FIGS. 9 a and 9 d , collector waveguide 1020defines a passage maze 1024 that includes an input cavity 1028 (severalof which are individually designated) in optical communication with exitport 1014 of one of horns 1008 (FIG. 9 a ). Input cavities 1028 can beimpedance matched to exit apertures 1014. Waveguide maze 1024 defines awave passage that leads from each input cavity 1028 to a combined output1030 (FIG. 9 d ). The combined output can be impedance matched to aninput 1038 (FIG. 9 b ) of detector 88. It is noted that a lower surface1032 of horn layer 1004, when received on collector waveguide 1020 asshown in FIG. 9 a , serves as a lid to define one side or sidewall ofthe wave passages to complete and enclose the wave passages. In thepresent embodiment, input cavities 1028 are arranged in groups of four1040, one of which groups is surrounded by a dashed box in FIG. 9 d . Inthis embodiment, the path length through waveguide maze 1024 from anyone of the input cavities to combined output 1030 is essentiallyidentical in terms of passage length. Collector waveguide 1020 can beformed in any suitable manner and from any suitable material(s). In anembodiment, the collector waveguide can be formed from a sheet material.Suitable methods for producing the collector waveguide include but arenot limited to molding, machining, and 3D printing, while suitablematerials include but are not limited to brass, aluminum, steel, andmetal-coated plastic. These materials can be coated or plated, forexample, with a layer of nickel followed by a layer of gold.

Referring briefly to FIG. 9 e , a diagrammatic partially cutaway view,in perspective, of a modified collector layer is illustrated, generallyindicated by the reference number 1000′. Modified collector layer 1000′is the same as collector layer 1000 with the exception that wavepassages of waveguide maze 1024 can be partially or completely filledwith a dielectric material 1042 such as, for example, alumina and/orferrite. In an embodiment with the waveguide maze filled by adielectric, the waveguide interior (i.e., the passages of the waveguidemaze) can be formed, for example, by injection molding or 3D printedusing a dielectric such as plastic and then the waveguide exterior canbe plated onto the exterior of this structure to form conductive walls.

FIG. 9 f is a diagrammatic partially cutaway view, in perspective, of amodified collector layer, generally indicated by the reference number1000″. Modified collector layer 1000″ is the same as collector layer1000 with the exception that horn layer 1004 has been replaced by a lenslayer 1050 that is made up of an array of convex lenses, several ofwhich are individually designated by the reference number 1054. Lenses1054 can be supported by a suitable dome 1058 in a manner that isconsistent with like structures described herein. Bases 1060 supportingdomes 1058 can define a conical horn 1064 having an aperture thatcouples to a passage of waveguide maze 1024, although a conical horn isnot a requirement and any suitable shape can be used.

Referring to FIGS. 10 and 11 , FIG. 10 is a diagrammatic partiallycutaway view, in perspective, of another embodiment of a systemconfigured in accordance with the present disclosure and generallyindicated by the reference number 1100 while FIG. 11 is a diagrammaticpartially cutaway and exploded view, in perspective, of system 1100.Processor 54, display 94 and input device 96 have not been shown forpurposes of illustrative clarity but are understood to be present.

Initially, it is noted that concentration layer 404 and modulation layer420 are essentially the same as the corresponding layers shownoriginally in FIG. 4 with one exception that FIGS. 10 and 11 illustratean 8×8 array rather than a 3×3 array. The reader is referred to thedescriptions of these layers, which appear above, and such descriptionswill not be repeated for purposes of brevity. It is also noted thatdetector 88 is unchanged with respect to its appearance in FIG. 4 . Asanother exception a collection layer 1110 is arranged for directtransfer of energy from modulation layer 420. The term “direct transfer”is utilized to refer to embodiments that do not require an exit layer.In other words, modulated light is carried or delivered from themodulation layer directly to the collection layer. The collection layerincludes previously described collector waveguide 1020 upon which acollection lid 1114 is receivable. A distal end 1120 (FIG. 11 ) of eachlower dielectric post 440 is received through a corresponding aperture1124 that is defined by lid 1114. In this regard, is noted that thecollection lid serves to complete one side of the passages that aredefined by waveguide maze 1024 of the collector waveguide. A printedcircuit board is understood to be present for driving modulators 424 buthas not been shown for purposes of illustrative clarity. Distal ends1120 (FIG. 11 ) of lower dielectric posts 440 are positioned for directtransfer of modulated electromagnetic energy to cavities 1028 of thecollector waveguide that is then combined enroute to the detector (seeFIG. 10 ). Collection lid 1114 can be formed from any suitablematerial(s) including, but not limited to brass, aluminum, steel, andmetal-coated plastic.

In another embodiment, each dielectric post 440, along with anyjacketing provided, can extend only partially through apertures 1124such that a lowermost portion of each aperture serves as a waveguide. Inthis regard, collector waveguide 1020, by way of non-limiting example,can be formed from a suitable waveguide material or the lowermostinterior wall of the aperture can be coated with a suitable waveguidematerial. The lateral extents of the aperture can be configured at anupper end to receive posts 440 and change along the length of theaperture to the lower end thereof to account for impedance matchingconsiderations leading into cavities 1028.

FIG. 12 is a diagrammatic view, in perspective, illustrating anembodiment of an optoelectronic system, generally indicated by thereference number 1200 and produced in accordance with the presentdisclosure. System 1200 can include sensor 88, for sensingelectromagnetic radiation of interest such as, for example, millimeterwave (MMW) radiation 1204 from a scene 1208 that is of interest. It isnoted that electromagnetic radiation 1204 may be referred to as inputlight. The input light is incident upon a concentration layer 1210which, in this example is an array of horns with several concentratinghorns of the array individually designated by the reference number 1214.It is noted that, in another embodiment, concentration layer 1210 can bemade up of an array of lenses such as convex lenses. Benefits associatedwith concentration layer 1210 will be discussed at an appropriate pointhereinafter, once the reader has been provided a complete overview ofthe remaining components of system 1200. After passing throughconcentration layer 1210, concentrated input light 1218 travels to amodulation layer that includes a spatial light modulator 1220.

Referring to FIG. 13 in conjunction with FIG. 12 , the former is afurther enlarged, diagrammatic perspective view illustrating additionaldetails of spatial light modulator 1220 of FIG. 15 and its interface toprocessor 54. It is noted that FIG. 16 appears as FIG. 2 a in U.S. Pat.No. 10,698,290, entitled ADVANCED BLOCKING PATTERN STRUCTURES, APPARATUSAND METHODS FOR A SPATIAL LIGHT MODULATOR, which is incorporated hereinby reference and hereinafter referred to as the '290 patent. In thisembodiment, the spatial light modulator includes first and second reels,spindles or spools 1260 a and 1260 b, respectively, each of which issupported for bidirectional rotation as indicated by arcs 1264. Reel1260 a can be bidirectionally driven by a first motor 1266 a, asindicated by a double headed arrow 1268 a, while reel 1260 b can bebidirectionally driven by a second motor 1266 b, as indicated by adouble-headed arrow 1268 b. In the present embodiment, motor 1266 a is astepper motor while motor 1266 b is a DC motor such that a flexibleblocking pattern tape or ribbon 1300 can be spooled bidirectionallybetween reels 1260 a and 1260 b, as indicated by a double headed arrow1304. It is noted that reels 1260 a and 1260 b along with associatedmotors 1268 a and 1268 b may be referred to herein as a flexible tapetransport. A free or lateral portion 1306 of the tape extends betweenreels 1260 a and 1260 b. In addition to a blocking pattern 1310, tape1300 can carry an upper servo stripe 1314 a along each its upperlengthwise edge margin and a lower servo stripe 1314 b along its lowerlengthwise edge margin, each servo stripe including suitable servo marks1318, as will be further described. The servo stripes may be referred tocollectively using the reference number 1314. It is noted that the servostripes and blocking pattern carry around spooled portions of tape 1300on reels 1260 a and 1260 b, however, this has not been shown due toillustrative constraints. It is also noted that a grid 1319 defining theindividual cells of the blocking patterns shown in FIGS. 12 and 13 isprovided by way of illustration for purposes of descriptive clarity andis not required. The tape transport of FIGS. 12 and 13 , like relatedembodiments brought to light in the '736 application employ at least oneflexible tape, including at least one linear portion (e.g., free portion1306) along which the flexible tape is moved linearly in a plane along alengthwise dimension and a non-linear portion which, in the presentembodiment are end portions of the flexible tape spooled on reels 1260 aand 1260 b. It is noted that the teachings that have been brought tolight herein are equally applicable with respect to embodiments thatutilize two flexible tapes. In the present embodiment, at least aportion of the overall tape transport path is nonlinear. First andsecond upper readers 1320 a and 1320 b, which may be referred tocollectively as upper readers 1320, are supported to read the upperservo stripe while first and second lower readers 1324 a and 1324 b,which may be referred to collectively as lower readers 1324, aresupported to read the lower servo stripe. It is noted that the upper andlower readers are supported independent of the support for motors 1266 aand 1266 b such that the readers detect relative movement of the tapewhich can be, for example, movement of the tape up and down on reels1260 a and 1260 b or even relative vertical movement of these reelsthemselves. In some embodiments, only one servo stripe is needed, alongwith its associated readers. Each reader can operate, for example, basedon emitting light from an LED and receiving the emitted light using aphotodiode or phototransistor on an opposing side of the ribbon. It isnoted that, due to the use of stepper motor 1266 a, servo stripes 1314and the associated readers can be optional, as will be furtherdiscussed. In another embodiment, motor 1266 a, like motor 1266 b, canbe a DC motor in which case, servo stripes 1314 and the associatedreaders are required. In still another embodiment, a tensioningarrangement can maintain a suitable amount of tension on tape 1300. Sucha tensioning arrangement, for example, can comprise a roller or rodmovable by a linear stage such that movement in one direction engagesthe flexible tape to increase tension while movement in an oppositedirection reduces tension. Controller computer or processor 54 caninclude monitor 92 and input device 94. In FIG. 12 , an interface 1350is connected to spatial light modulator 1220 to provide electricalcommunication with controller computer 54. A sensor signal line 1354provides signals from sensor 88 to controller computer 54. As seen inFIG. 13 , interface 1350 includes a first reader interface 1360 fromupper servo readers 1320 a and 1320 b and a second reader interface 1364from lower servo readers 1324 a and 1324 b. The reader interfaces canprovide an individual signal from each reader to processor 54 which canprovide information relating to the status of flexible blocking patterntape 1300 such as, for example, being indicative of buckling along freeportion 1306. It is noted that power supply lines for the readers andother components have not been shown but are understood to be present.Drive signals for motor 1266 a are provided by a first motor driveinterface 1368 while drive signals for motor 1266 b are provided by asecond motor drive interface 1370. It is noted that the spool size(i.e., diameter) for reels 1260 a and 1260 b can be selected to balancevarious factors. For example, a relatively larger spool size (i.e.,greater diameter) will result in lower stress on flexible tape 1300,leading to longer life. On the other hand, such relatively larger reelsconsume more space and are likely more heavy.

As seen in FIG. 12 , a portion 1372 of electromagnetic wave radiation orinput light (i.e., a portion of incident radiation 1218) emerges fromtape 1300, indicated by arrows, and travels toward sensor 88 forcollection by a horn 1374 and concentration onto this single pixelsensor such that horn 1374 serves as a collection layer. FIG. 13illustrates an exposure region 1400 that is planar and indicated by aheavy, dashed line, such that at least a portion of radiation 1218 (FIG.1 ) passing through region 1400 is collected and, thereafter, incidenton sensor 88. In the present example, region 1400 forms a blockingpattern that is made up of a 6×6 array of cells. Generally,electromagnetic radiation that transits through tape 1300 outside ofregion 1400 such as, for example, through the servo stripes is rejected.

During operation of system 1200, stepper motor 1266 a is driven bycontrol computer 54 to controllably release or take up tape 1300 toselectively establish the lateral segment of the tape that makes up theblocking pattern appearing in region 1400. At the same time, controlcomputer 54 drives DC motor 1266 b to maintain at least some degree oftension on free or suspended portion 1306 of the tape extending betweenreels 1260 a and 1260 b, thereby ensuring that the free portion remainssufficiently planar or flat (i.e., linear). In this way, motors 1266 aand 1266 b can cooperatively and precisely position a series ofdifferent blocking patterns within region 1400 with controller computer54 capturing a reading from sensor 88 in association with each of thedifferent blocking patterns. As will be further discussed, there will besome amount of tolerance in the precision of positioning a particularblocking pattern on tape 1300 within exposure region 1400. In thisregard, system 1200 provides a heretofore unseen approach in dealingwith this tolerance, as will be further discussed.

Turning the reader's attention back to concentration layer 1210, itshould be appreciated that one concentrating horn 1214 of the horn arrayis aligned with each cell of any given blocking pattern of tape 1300that is positioned in exposure region 1400. An input aperture 1404 ofeach concentration horn that faces scene 1208 includes essentially thesame lateral dimensions as the corresponding cell. That is, the lateraldimensions are length and width in a direction transverse to thedirection of travel of input light 1204, as shown. Each concentrationhorn 1208 further includes an output aperture 1408 that is smaller inlateral dimensions that the corresponding cell of the blocking pattern.Assuming perfect alignment of the blocking pattern in exposure region1400, concentrating horns direct their concentrated output light 1218onto a central region of the cells in the blocking pattern. Centralregions 1410 of two adjacent cells are illustrated as rectangles in FIG.13 under the assumption of perfect alignment. Accordingly, theconcentrated output light is incident upon each cell spaced away fromthe actual edges of the cell when there is perfect blocking patternalignment. Thus, at least some tolerance for misalignment of theblocking pattern within the exposure region is provided by a marginaround the edges of the cells, since the blocking pattern can shiftside-to-side and/or up and down at least to some extent without theconcentrated input light moving beyond the margins and spilling onto anadjacent cell of the blocking pattern. The reduction in requiredprecision in movement of tape 1300 can translate into a number ofdifferent benefits. For example, cost can be reduced by loweringtolerance requirements for positioning of tape 1300. As another example,structures can be incorporated into tape 1300 within the inter-cellmargins. In an embodiment that uses a clear (i.e., transparent)substrate to form tape 1300 with deposited metal to form the blockingpattern, the plated area can be made smaller to approximately match thesize of central regions 1410 and/or the clear substrate can be maderelatively thinner in central regions 1410 to enhance electromagneticenergy transfer while maintaining the substrate relatively thickeroutside of the central regions to enhance strength.

It should be appreciated that tape 1300 can be moved in either directionby the motors. Reels 1260 a and 1260 b, as is the case with reels inother embodiments, can include features to guide the tape, such ascontours, steps, texturing and/or flanges. In some embodiments, tape1300 is moved the full width of exposure region 1400 from one blockingpattern to the next in the series, while, in other embodiments, the tapecan be moved by an incremental amount that is less than the full widthof region 1400 from one blocking pattern to the next. It is noted thatan incremental movement can be as small as the width of one cell of theblocking pattern. Movements by some multiple number of cell widths mayproduce a more acceptable change from one blocking pattern to the next,especially given Applicants' recognition that real life scenes tend tobe self-correlated. In any embodiment that employs a flexible blockingpattern tape, a tape transport supports the flexible tape(s) formovement to transit the tape linearly through the electromagnetic energyin exposure region 1400 as the electromagnetic energy is traveling fromthe antenna to the single pixel sensor. At the same time, the flexibletape moves on a tape transport path that is, at least in part, nonlinearoutside of the exposure region.

Still referring to FIGS. 12 and 13 , flexible blocking pattern tape 1300includes a flexible substrate that is transmissive at the wavelength ofinterest. Suitable materials for visible light include, but are notlimited to Novele and Polyethylene terephathalate (PET). Suitablematerials for millimeter wave (MMW) radiation include, but are notlimited to polyimide, PET, and Novele. Thus, transmissive cells areessentially comprised of the substrate material itself with noadditional coatings or materials. For the “black” or non-transmissivecells, metallic coatings such as, for example, copper and silver canreadily be made flexible at required thicknesses for wavelengths fromoptical to MMW radiation. The coatings can be applied to form thedesired pattern on the substrate, for example, by electrodepositionthrough a mask, roll-to-roll processing, sheet deposition followed bychemical etching, and ink jet printing. It is noted that any suitabletechnique can be employed and that the size or dimensions of the cellscan be suited to any desired wavelength. In another embodiment, the tapecan be formed from a thin flexible metal such as, for example, steelhaving holes or apertures formed therein to define the transmissivecells of the blocking pattern. This latter embodiment can be very robustand can be suited to any desired wavelength by changing the dimensionsof the cells. Moreover, enhanced stiffness, as compared to a plasticsubstrate, can enhance controllability.

Having described structural details of spatial light modulator 1220above in the context of system 1200, it is appropriate at this junctionto consider aspects of its operation. Generally, a set or series ofblocking patterns is used such that a sensor output is recorded for eachblocking pattern of the series. Relative increases in the number ofblocking patterns in the series as well as increasing the number ofcells that change or toggle between a transmissive status and anon-transmissive status from one blocking pattern to the next can serveto enhance image resolution and clarity. Any suitable series of blockingpatterns can be used such as, for example, Hadamard patterns or randomlygenerated patterns. To generate an image, controller computer 54actuates motors 1266 a and 1266 b to move tape 1300 such that a desiredblocking pattern is positioned in exposure region 1400. An initial orbeginning blocking pattern can be the first pattern proximate to one ofthe opposing ends of the tape, although this is not a requirement.Controller computer 54 reads the output of sensor 88, for example, viaanalog to digital conversion of the sensor voltage output, and savesthat converted output. In the present embodiment, the sensor value iscaptured when tape 1300 is stationary. In some embodiments, it is notnecessary for the tape to be stationary based, at least in part, on thecharacteristics of the particular sensor that is in use. If anotherblocking pattern is needed for generating the image currently inprocess, controller computer 54 moves tape 1300 and thereby a newblocking pattern into exposure region 1400 and then obtains a new sensoroutput. This process repeats until a complete set of sensor outputs isobtained for use in generating an image.

It should be appreciated that multiple instantiations of systemsdescribed above can be positioned in a side-by-side relationship andused in coordination for purposes of generating an image. By way ofnon-limiting example, systems that utilize aforedescribed collectorwaveguide 1020 as an element of their structure can readily bepositioned side-by-side. FIG. 14 is a diagrammatic partially cutawayview, in perspective, illustrating four collector waveguides designatedas 1020 a, 1020 b, 1020 c and 1020 d side-by-side for use as part of anoverall system generally indicated by the reference number 1420. Thecollector waveguides may be referred to collectively as collectorwaveguides 1020. Associated systems are partially shown in phantom usingdashed lines and indicated by the reference numbers 1100 a-1100 d. Eachof systems 1100 a-1100 d includes a detector 88 a-88 d and a collectorwaveguide 1020 a-1020 d, respectively. It is noted that collectorwaveguides 1020 a and 1020 b are shown as partially cutaway to revealassociated detectors, while the detectors associated with collectorwaveguides 1020 c and 1020 d are not visible but are understood to bepresent. The detector associated with each collector waveguide can becoupled with processor 54 (not shown) which can also control any lightmodulators that are in use in a manner that is consistent with thedescriptions above. Systems 1100 a-1100 d can be referred to as spatiallight modulation modules such that each module is individuallyreplaceable and/or individually usable. For example, given that anysuitable number of spatial light modulation modules can be used,different fields of view can be provided by using different combinationsof modules. As another example, manufacturing benefits are providedsince the production yield on a light modulator having a relativelysmaller light modulator array will be significantly higher than theyield on a light modulator array that is some number of times larger(e.g., using nine 16×16 modular arrays to make up an overall 48×48modulator array.) Moreover, Applicant recognizes that the productioncosts associated with nine 16×16 modular arrays are lower than thoseassociated with one 48×48 array. As another example, since each 16×16module includes a dedicated detector, the light modulation modules canbe operated in parallel to fill-in an image being generated faster andwith less loss than a corresponding system with a single detector.

FIG. 15 is a diagrammatic partially cutaway view, in perspective,illustrating collector waveguides 1020 a, 1020 b, 1020 c and 1020 dside-by-side for use as part of another overall system that is generallyindicated by the reference number 1440. Each collector waveguide 1020a-1020 d forms part of a sub-module designated as 1444 a-1444 d,respectively, and partially shown in phantom using dashed lines. Thesub-modules may be referred to collectively by the reference number1444. In the present embodiment, each of sub-modules 1444 a-1444 dincludes concentration layer 404 and modulation layer 420 (see FIG. 10 )in addition to one instance of collector waveguide 1020. It is notedthat collector waveguide 1020 a is shown as partially cutaway. Anuppermost outer periphery of the cutaway portion of collector waveguide1020 a as well as the entirety of collector waveguide 1020 b are shownin phantom represented by dashed lines so as to reveal underlyingstructure. In particular and instead of utilizing a detector for eachcollector waveguide, the present embodiment utilizes a supplementalwaveguide layer 1500 which includes an input from the collectorwaveguide of each sub-module. In the figure, supplemental waveguideinputs 1504 a and 1504 b are seen for collector waveguides 1020 a and1020 b, respectively. The supplemental waveguide inputs for collectorwaveguides 1020 c and 1020 d are not visible but are understood to bepresent. Supplemental waveguide layer 1500 defines a wave passage foreach collector waveguide leading to a combined output 1510 such that acombined output light 1514 is directed to detector 88 which is shown asbeing spaced away from the remaining structure for purposes ofillustrative clarity, although this is not required. Detector 88 iscoupled with processor 54 (not shown) which can also control any lightmodulators that are in use in a manner that is consistent with thedescriptions above. In view of the discussions of FIG. 14 , it should beappreciated that each of sub-modules 1444 can be replaced individuallywhile providing still further benefits with regard to reducingproduction costs by utilizing a dimensionally smaller light modulatorarray than the equivalent size of the overall array that is provided bysystem 1440.

The foregoing description of the invention has been presented forpurposes of illustration and description. It is not intended to beexhaustive or to limit the invention to the precise form or formsdisclosed, and other modifications and variations may be possible inlight of the above teachings. Accordingly, those of skill in the artwill recognize certain modifications, permutations, additions andsub-combinations of the embodiments described above.

What is claimed is:
 1. An optoelectronic system, comprising: aconcentration layer including an array of optical concentrators, eachoptical concentrator including a concentrator input area and aconcentrator output area that is smaller than the concentrator inputarea such that each concentrator concentrates a portion of an inputlight beam received at the concentrator input area into the concentratoroutput area; and a modulation layer including an array of electricallycontrollable light modulators that are spaced apart from one another inthe modulation layer for modulating each portion of the input light witheach light modulator having: (i) a modulator input area in opticalcommunication with the concentrator output area of one of the opticalconcentrators, and (ii) a modulator waveguide for receiving themodulated portion of light and externally outputting the modulatedportion of light; a collector waveguide defining a waveguide input forthe modulator waveguide of each light modulator in the array of lightmodulators and the collector waveguide combines the outputted modulatedlight from the array of electrically controllable light modulators toproduce a collector waveguide output; and a detector for receiving thecollector waveguide output to produce a detector output that isresponsive to the combined outputted modulated light.
 2. Theoptoelectronic system of claim 1 wherein the modulator waveguideincludes a dielectric post that is jacketed with an electricallyconductive layer for receiving the modulated portion of light from oneof the electrically controllable light modulators and for outputtingthat modulated portion to one waveguide input of the collectorwaveguide.
 3. The optoelectronic system of claim 1 wherein eachwaveguide input of the collector waveguide is impedance matched to themodulator waveguide of one of the light modulators.
 4. Theoptoelectronic system of claim 1 wherein the collector waveguide definesa plurality of waveguide paths such that each waveguide path leads fromone waveguide input to the collector waveguide output and the waveguidepaths are of the same length.
 5. The optoelectronic system of claim 1wherein the collector waveguide is integrally formed from a sheetmaterial.
 6. The optoelectronic system of claim 5 wherein the sheetmaterial includes at least one of brass, aluminum, and steel.
 7. Theoptoelectronic system of claim 6 wherein the sheet material defining thewaveguide paths is plated with a nickel layer and a gold layer.
 8. Theoptoelectronic system of claim 1 wherein the collector waveguide definesa plurality of waveguide paths such that each waveguide path leads fromone waveguide input to the collector waveguide output and the waveguidepaths are filled with a dielectric material.
 9. An overalloptoelectronic system, comprising: a plurality of side-by-sideinstantiations of the optoelectronic system of claim 1 such that eachinstantiation serves as a replaceable spatial light modulation moduleand the modules cooperate such that different combinations of theinstantiations produce different fields of view for generating an image.